Review reviewHigh

CVE-2026-54403

Ubiquiti Inc UniFi OS Server, Dream Machines, Enterprise Fortress Gateway

A malicious actor with access to the network could exploit a Path Traversal vulnerability found in certain devices running UniFi OS to bypass authentication of such UniFi OS devices or instances.

CVSS
8.6
EPSS
0.56%
43.1% percentile
CISA KEV
Not listed
Published
2026.07.03
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.56%
Technical severityCVSS 8.6

Vulnerability overview

A malicious actor with access to the network could exploit a Path Traversal vulnerability found in certain devices running UniFi OS to bypass authentication of such UniFi OS devices or instances.

Affected product and versions

Product
Ubiquiti Inc UniFi OS Server, Dream Machines, Enterprise Fortress Gateway
Affected versions
<= 5.1.15, <= 5.1.16, <= 5.1.18
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Ubiquiti Inc UniFi OS Server, Dream Machines, Enterprise Fortress Gateway and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
CWE
CWE-22
CVE-2026-54403 — Ubiquiti Inc UniFi OS Server, Dream Machines, Enterprise Fortress Gateway | SECUFOCUS NOW